more tests + small refactoring (no more App struct)

app/converter/process/process.go

@@ -0,0 +1,135 @@
+// Package process handles all commands executions.
+package process
+
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"text/template"
+	"time"
+
+	"github.com/gulien/gotenberg/app/config"
+	gfile "github.com/gulien/gotenberg/app/converter/file"
+)
+
+var commandsConfig *config.CommandsConfig
+
+// Load loads the commands configuration coming from the application configuration.
+func Load(config *config.CommandsConfig) {
+	commandsConfig = config
+}
+
+// conversionData will be applied to the data-driven templates of conversions commands.
+type conversionData struct {
+	FilePath       string
+	ResultFilePath string
+}
+
+type impossibleConversionError struct{}
+
+func (e *impossibleConversionError) Error() string {
+	return "Impossible conversion"
+}
+
+// Unconv converts a file to PDF and returns the new file path.
+func Unconv(workingDir string, file *gfile.File) (string, error) {
+	cmdData := &conversionData{
+		FilePath:       file.Path,
+		ResultFilePath: fmt.Sprintf("%s%s", gfile.MakeFilePath(workingDir), gfile.PDFExt),
+	}
+
+	var (
+		cmdTemplate *template.Template
+		cmdTimeout  int
+	)
+
+	switch file.Type {
+	case gfile.HTMLType:
+		cmdTemplate = commandsConfig.HTML.Template
+		cmdTimeout = commandsConfig.HTML.Timeout
+		break
+	case gfile.OfficeType:
+		cmdTemplate = commandsConfig.Office.Template
+		cmdTimeout = commandsConfig.Office.Timeout
+		break
+	default:
+		return "", &impossibleConversionError{}
+	}
+
+	var data bytes.Buffer
+	if err := cmdTemplate.Execute(&data, cmdData); err != nil {
+		return "", err
+	}
+
+	err := run(data.String(), cmdTimeout)
+	if err != nil {
+		return "", err
+	}
+
+	return cmdData.ResultFilePath, nil
+}
+
+// mergeData will be applied to the data-driven template of the merge command.
+type mergeData struct {
+	FilesPaths     []string
+	ResultFilePath string
+}
+
+// Merge merges many PDF files to one unique PDF file and returns the new file path.
+func Merge(workingDir string, filesPaths []string) (string, error) {
+	cmdData := &mergeData{
+		FilesPaths:     filesPaths,
+		ResultFilePath: fmt.Sprintf("%s%s", gfile.MakeFilePath(workingDir), gfile.PDFExt),
+	}
+
+	cmdTemplate := commandsConfig.Merge.Template
+	cmdTimeout := commandsConfig.Merge.Timeout
+
+	var data bytes.Buffer
+	if err := cmdTemplate.Execute(&data, cmdData); err != nil {
+		return "", err
+	}
+
+	err := run(data.String(), cmdTimeout)
+	if err != nil {
+		return "", err
+	}
+
+	return cmdData.ResultFilePath, nil
+}
+
+type commandTimeoutError struct{}
+
+func (e *commandTimeoutError) Error() string {
+	return "The command has reached timeout"
+}
+
+// run runs the given command. If timeout is reached or
+// something bad happened, returns an error.
+func run(command string, timeout int) error {
+	cmd := exec.Command("/bin/sh", "-c", command)
+	if err := cmd.Start(); err != nil {
+		return err
+	}
+
+	done := make(chan error, 1)
+	go func() {
+		done <- cmd.Wait()
+	}()
+
+	// wait for the process to finish or kill it after a timeout.
+	select {
+	case <-time.After(time.Duration(timeout) * time.Second):
+		if err := cmd.Process.Kill(); err != nil {
+			return err
+		}
+
+		return &commandTimeoutError{}
+	case err := <-done:
+		if err != nil {
+			return err
+		}
+
+		return nil
+	}
+}